Journal of KIISE:Computer Systems and Theory (한국정보과학회논문지:시스템및이론)

Korean Institute of Information Scientists and Engineers (한국정보과학회)
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Interactive Animation of Articulated Bodies using a Procedural Method

절차적 방법을 이용한 다관절체의 대화형 동작생성

  • Published : 2001.12.01
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Abstract

In interactive environments including computer games and virtual reality applications, we have increased need for interactive control of articulated body motions. Recently, physically based methods including constrained dynamics techniques are introduced to this area, in order to produce more realistic animation sequences. However, they are hard to achieve real-time control of articulated bodies, due to their heavy computations. In this paper, we present a procedural method for interactive animation of articulated bodies. In our method, each object of the constrained body is first moved according to their physical properties and external forces, without considering any constraints. Then, the locations of objects are adjusted to satisfy given constraints. Through adapting this two-stage approach, we have avoided the solving of large linear systems of equations, to finally achieve the interactive animation of articulated bodies. We also present a few example sequences of animations, which are interactively generated on PC platforms. This method can be easily applied to character animations in virtual environments.

게임이나 가상 현실 등의 대화형 처리에서 다관절체의 동작을 실시간으로 처리할 필요성이 증가하고 있다. 최근에는 다관절체의 동작을 사실적으로 표현하기 위하여, 제약 동역학(constrained dynamics)방법들이 사용되고 있으나, 이 방법들은 사용자의 요구가 빈번한 가상 공간에서 다관절체의 동작을 실시간으로 처리하기는 곤란하다. 본 논문에서는 다관절체의 동작을 비교적 사실적이면서도 빠르게 생성하기 위한 절차적 방법(procedural method)을 제안한다. 이 방법에는 다관절체를 구성하는 세그먼트들의 동역학적 움직임과 조인트에서의 기하학적 제약 조건을 따로 처리함으로써, 복잡한 선형 시스템의 풀이 과정을 피하였다. 결과적으로 본 본문이 제안하는 방법은 필요한 계산량을 줄임으로써 실시간 처리가 가능하다. 제안하는 방법의 구현 결과로서, 일반적인 PC 환겨에서 인형 형태 다관절체의 동작을 대화형으로 실시간에 처리할 수 있음을 보인다. 이러한 방법들은 가상 공간에서의 캐릭터 애니메이션 등에 적용할 수 있을 것으로 기대된다.

Keywords

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